Automatic tuner



.Je w, 1 93 LE ROY J. LEISHMAM AUTOMATIC TUNER? Filed Nov. 22, 1957 2' Sheets-Sheet 1' my 1939- I LE ROY J. LEusHMAM 2,162,282

I 7 AUTOMATIC TUNER Filed Nov. 22, 1937 2 She et s-Sheet- 2 Patented June" 13, less 2,162,282 V I A'Uromrrc TUNER Le Roy 1. Los Angeles, Calif. Application November 22,1931, Serial No..175,916

11 claims. (01. 14-10) This invention relates to radio receiving sets a. long side C, ashort side '1, and a horizontal top and the hire, and more particularly to those in section D connecting sides T and 'C. Shafts S which the tuning control'shaft is turned to preand Q are journaled. at one end in the side, or determined angular positions by semi-automatic end plate, C, and at the other end in plate I. means. Among its objects are conservation of The semi-automatic tuning mechanism proper, 5 space, simplicity of construction, the provision shown in Fig. is a modification of the mechaof means whereby it is rendered difiicult to see the ni ln ill tr ed, de cri e n l m n my apparatus through apertures in the escutcheon, Pending p a 154,819- The alterthe illumination oi the station index tabs by the a i s n t s mechanism r u s space requiree same bulbs illuminating the dial, the exclusion m n s n pe mit r pe a i n ,:W 11 10 of light from the semi-automatic operating mechaccurate workmanship in the manufacture of the anism, and the provision of a manual tuning Darts. Operating lever F is provided with a midcontrol that does not make the semi-automatic s ct having a fia uppe d e 2 that normally controls more dimcult to operate. Still other obis held against abutment P by sp in J festened n iects will appeal: as the description proceeds. h s 3 n e drawn po n 4 of p a This 15 In t accompanying drawingsg portion is depressed so that the hooks on the ends Fig. 1 is a side elevation of my device, with f the springs will not extend a ov h p part of the radio chassis cut awa to reveal the face of Plate h a utm t P may bev mad constructi n m r clearly, of rubber or other resilient material, and is ce- 20. Fig. 2 shows the design of the operating levers merited or otherwise attached to e under side and positioning cams, together with their relation of Plate to t top cover of t device At portion 6, Fig. 2, lever F forms substan- Fig. 3 is a side elevation of the frame for the tielly e same angle i p siti na er A mechanism, showing the pulleys and gears that in the illustrated upward p si ion as it does in 5 are on the opposite side to that shown in Fig; 1. the form shown in 3 f y De ng app i- Fig 4 1 a front elevation th various parts cation above referred to. In front of position 6,

cut away to reveal the construction more clearly. the loweredge of level F curves downward. as Fig. 5 is a plan view of the manual drive of Fig. 4. shown at s leVeIfF is pressed w aus n Fig 6 is a pgj'spective View qf a chassislstamped end I of positionable member, orlever, A' to move t t accommodate t t at tuning device outward along lever F, the angle between the two Fig. 7 illustrates a novel means of attaching the engaglng levers is such that v l A moves easily tuning mechanism t t indicator for a vertical despite the downward curve or arch 5 in the lower tuning 3031a edge of lever F. When lever F is depressed as Fig. Bisa front elevation ofahorizontaltlming e as it Will 8 r h 5 erves a very useful scale, showing an improved pulley system tor con- P This extreme Position of 811 Ope a ing 35 necting the indicator to the tuning mechanism. leverlsshown by lever i 2, cooperating with L Fig. 9 is a side elevation of the pulley arrangepositionable 1eVel The m t oflev r F ment shown in Fig. '7, v has turned member Al until the two levers are in w a ]ever operated tuning mechanism engagement at two'points 8 and 9'. Arch 5a of 40 placed on top of the chassis, with the currently-' is e n to be curved away f the popular large round dial above t tuning mech stantlally straight adjacent edge of member Al,

' anism,the. distance from the bottom of the chassis assuring that the enga m n between the two t t top 0f th dial is t greai; for average cooperating levers will be at points 8 and 9only, height table model receiving sets This mven- This obviates the possibility of manufacturing in-.

tion makes it possible to put the lever-controlled accuracies causing illese levers to engage a ome operating mechanism on the, underside of the mtervenlng 90mlthus destroying e Pr n f chassis; thus greatly reducing the over all height h angular position to whi h member Al is oi the complete assembly. Placing the mecha-. always turned when lever Fl is pressed l nism under the chassis is also an aid in keeping way down- I I light from th dial-illuminating lamps fr The center portion lla of positionable member 50 illuminating th apparatus a making it visible Al is split through the hole that admits shaft S through the lever slots in the escutcheon. in Order t0 form clamp 9 emxihg mellrlbel'v Al In.1='ig 1, w is th having a top 3 to the shaft in any desired angular position. (partly shown in section) to which is attached the when the operating level is pressed 1 h W y top place D of the tu er assembly n by down, thus rotating member Al to the position means 9f s ews E and nuts 95. shown, it will be noted that the clamping screw In the form shown in the 'drawings, t frame RI is substantially horizontal and parallel to the 1 is constructed from two pieces-part I, which to!) plate D; forms the side in which the short shafts for gears A plurality of operating levers, preferably L and Y are iournaled; and a second part having having buttons on the free ends; a e mounted so by means of pins 26 attached to pulley 32 at point 33,

on rod Q, and each operating lever cooperates with one of a series of positionable members on shaft S.

In Fig. 1, a positionable lever A2 is shown in an angular position 180 degrees opposite from that occupied by positionable member A as illustrated in Fig. 2. It will be noted that the rounded end K2 is so shaped that the downward movement of lever F will cause positionable member A2 to assume the position shown in dotted lines. This is the tuned-in position just described in relation to Fig. 2the position at which the further down-I ward movement of the operating lever is arrested by engagement with the positionable lever at two points lying on opposite sides of the shaft S.

The motion of shaft S must be transmitted to the impedance varying means-in this case the gang condenser 2|, Fig. 4, and to the tuning scale or indicator.

The connection to the condenser is efiected by means of gear l2, Fig. 4, attached to shaft S by screw i3 in hub l4; idler gear Y, Figs. 1, 3 and 4, meshing with gear l2; gear L, meshing with gear Y, and attached to shaft I5 journaled in end-plate I; and the coupling i6 attached to shaft l5 and the condenser shaft i1. Pulleys l8 and. i9, having a l-2 ratio, are attached to gears L and i2 respectively, which also have this same ratio respectively. Since the type of semi-automatic tuning mechanism illustrated in Figs. 1 and 2 .turns only 90 degrees, this ratio is necessary to produce the required 180 degree rotation of the condenser. Cord 20 is attached to pulley l8 and to spring 23, which in turn is connected to cord 22 attached to pulleyv l9. The tension of spring 23 takes the play out of the gear train.

The transmission to the dial or pointer can best be explained with reference to Fig. 4. This figure is a front view of part of a radio set with portions of the escutcheon, cabinet, and light-excluding mask (to be explained later) cut away in order to show pulleys 24 and 25 fastened on shaft S on either side of the center positionable lever A and 28 respectively in short hubs 21 and 28 respectively. A- cord 30 is attachedto pulley or reel 24 at point 3| and to pulley 32 at a pointnot shown. Cord 34 is also but is reeled around the pulley in an opposite direction to that of cord 30. Cord 34 is fastened to spring 35, which is attached at its opposite end to cord 36. Cord 36 passes around pulley 25 as indicated in the figures and is attached to this pulley at a position not shown. Spring 35 keeps the cords taut. Pulley 32 is attached to shaft 31 by means of set-screw 38. Shaft 31 may be attached to a rotating dial, or, as shown in Fig. 1, to an indicating hand 39, which requires that the shaft pass through the center of dial 40. Pulley 32 may have any desired ratio with respect to pulleys 24 and 25 in order to move the indicating hand around the calibrated portion of the dial during the 90 degree rotation of shaft S.

Cords 30 and 36 pass through holes in plate I) of the tuner assembly frame, and through slots 42 and 4| respectively in the top of the chassis, shown in Fig. 6, which illustrates how the chassis is cut to accommodate the tuner assembly.

To operate a tuner of this type, it is desirable that ,very little pressure he required on the operating keys. The conventional types of drives between the manual tuning knob and the condenser shaft add enormously to the pressure that the operators finger must exert in order to move the interconnected mechanism. This invention provides a simple means whereby the manual drive is disconnected excepting when the operator is actually using the tuning knob. A beveled-edged wheel 43 is mounted on shaft S as indicated in Figs. 1, 4 and 5. A small wheel 44 having a rim of rubber or other material with suitable frictional properties is carried by a shaft 45 passing through holes 46 and 41 in the outer ends of bracket 48 attached to plate 0 of the tuner assembly frame. A collar 49 is attached to shaft 45 by pin or screw 50. An expansion spring Si is coiled around shaft 45. of this spring is supported against end 52 of bracket 48, and the other end of the spring forces collar 49 against end 53 of the bracket, as shown in Figs. 1 and 5. In this position of the shaft, the rim of wheel 44 is just out of engagement with the beveled edge 54 of wheel 43. The manual tuning knob 55 is preferably so shaped that the operator's fingers naturally press against it in order to secure a firm grip. This pressing action causeswheel 4% to engage the bevel of wheel @3, and the rotation of the knob thus turns wheel 43 and the interconnected tuning condensers and dial.

One of the objects of this invention is to keep the light that illuminates thetlial from illuminating the automatic tuning mechanism, as the mechanism is then visible through the lever slots in the escutcheon. Since the dial lamps are above the chassis, the placing of the lever mechanism below the chassis eliminates the greater part of this light, but still additional means have been provided for its exclusion. A mask, or subescutcheon, 56 is attached to the front of the tuner assembly in any suitable manner. This mask has slots GI for the levers and holes 51 for adjusting the positionable lever set-screws in a manner to be explained later. The mask 56 preferably extends above the chassis. The front plate or escutcheon 58 carries a perpendicular member 59 which serves the two-fold purpose of registering the escutcheon with the levers and adjusting screws regardless of the separation between the escutcheon and chassis, and of keeping light from above the chassis from shining through the slots in the escutcheon. This perpendicular member 59 rests on the top edge of mask 56, and the right end of the perpendicular member abuts against bracket 60, as shown in'dotted lines in Fig. 4. The portion of mask 56.that extends above the chassis not only forms part of the registering means, but also serves to keep light from the dial illuminating lamps 6| from passing. beneath member 59. The greater portion of the sub-escutcheon lying beneath the top of the chassis acts as a two-way mask. A certain amount of light from outside the radio set natu rally passes through the slots G in the front escutcheon and spreads out at a rather wide angle on the reverse side of the escutcheon. None of this light can reach the tuning mechanism excent the small portion that passes through the slots GI in the mask. In similar manner, the mechanism is rendered more difficult to see from the outside of the set because of the very narrow angle that would be visible through two slots in alignment as compared with only one.

Each operating lever is provided with a translucent index tab 0, Figs. 1 and 4, resting in a recess 62, Fig. 1, between plate M and escutcheon 58. Plate M is provided with a window N for each index tab. Lamps 6| that illuminate the dial also illuminate the index tabs.

To set the tuner so that each lever will tune One end holes This permits shaft S to turn freely while the popressure of the operating lever, which the operator continues to hold down. The desired station is then tuned in manually by means of knob 85. After the station is tuned in as perfectly as possible, the set-screw is again tightened. This procedure is repeated with each lever until they have been set" to tune in the operator's favorite stations. From the description already given of the workings of the operating levers and po-' sitionable members, it will be obvious that the subsequent pressing of any lever will perfectly tune in the station for which the setting was made.

Buttons 55 are removable from the endsof the operating levers, permitting the levers to pass freely through the slots G in the escutcheon. When this feature is borne in mind, it will be evident that the tuning unit without the escutcheon 9 may be completely assembled before mounting it on the chassis. The assembly frame of the tuner is provided with a rod or support i5 running from plate I to plate C to give it rigidity. This rod is omitted from Fig. 4 to avoid confusion with the other parts shown.

Part I of the assembly frame has a top section 6I bent at a right angle to the portion of membet I that supports the gears. Section 81' is stamped with projections 68, and 88 that are turned to form the'bracket in which the dialshaft 31 is journaled. Bracket 80 maybe stamped from the piece of metal forming the mainbody of the tuner frame, or it may be a separate piece. -In the form shown in the drawings, bracket 68 is integral with the frame, and is bent at the top to form a brace III for attachment in {any suitable manner to member 61.

Fig. 6 illustrates how the chassis is stamped to receive the tuning unit. As already explained,

slots 4| and 2 permit cords 36 and 88 respectively to pass. Slot II is for side I- of the tuner frame. Hole 12',- Fig. 6, receives bolt ll, Fig. 4,

which also passes through hole 15, Il-"ig. 3, in-

bracket I6; Figs. 3 and 4, formed on part I. Hole II in the chassis, Fig. 6, registers with hole 'l'l, Fig. 3, in bracket I8 on member I to receive a bolt for attaching the tuner assembly to the chassis. Holes 19 and 88 in the chassis, Fig. 6, are to receive screws E, Fig. 1. r

Fig. 7 shows the means and method of connecting the tuning imit to the indicating pointer,

for a vertical tuning scale. All parts of the unit have been omitted with the exception of shafts S, Q and I5 so that the relationship of these per tinent parts will not be obscured by other parts I of the tuner. In this embodiment of the invention, a series of operating levers are mounted on each end of rod Q on opposite sides of the vertical scale 8|, and a series of positionable-members are similarly mounted on each end of shaft S. The gang condenser should be positioned behind the vertical scale. Pulley 82 is mounted on shaft I5 and carries cords 88 and 88 which pass around pulleys 8i and 88 respectively. Cord U and 51, and set-screw R is loosened.

relative position between there are only three pulleys in all. sitionable member is being held stationary by the Fig. 8 illustrates a drive for a horizontal scale. Such a scale should preferably be placed above the tuning levers. In the figure, all parts of the tuner have been omitted with the exception of those that show the relationship of the parts associated'with the drive for the pointer. Pulley 82 is shown on shaft I5 between pulley l8 and coupling l8, which are located, along with the gang condenser, in the same positions shown in Fig. 4. Pulley 82, Figs. 8 and 9, carries a cord 84, fastened at a position 8|. After passing under pulley 82, this cord passes over pulley 88 and thence to a connection with pointer-mounting 82 for pointer 88 adapted to move along horizontal scale 94. Cord 83 is connected to the other end of the pointer mounting and passes around pulley 98 and then to cord-tightening spring 88. The other end of this spring is connected to one end of cord 84, which then passes around pulley 85. and thence to pulley 82.

'Although the preferred form of my invention contemplates the use of the lever-operated tuning mechanism hereinbefore described, other automatic or semi-automatic tuning-mechanisms may be used beneath the 1. In a device for positioning a control of a radio set, a combination including: a supporting element; an escutcheon positioned substantially at right angles to saidsupporting element; a rotatable shaft positioned beneath said supporting element and lying substantially parallel to said escutcheon and to saidsupporting element; a calibrated scale and indicator positioned above said supporting element; means for varying the said indicator and the calibrations on said scale in accordance 'with the angular position of said shaft; and a member extending substantially perpendicularly from said escutcheon; said member and said supporting element overlapping.

2. In a device for radio set, a combination including: a supporting element; an escutcheon positioned substantially at right angles to said supporting element; a rotatable shaft positioned beneath said support-- ing element'and lyingsubstantially parallel to' said escutcheon and to said element; a calibrated.

positioning a control of a neath saidsupporting element and lying beneath and, substantially parallel to said element; a plurality of operating levers pivoted beneath said element; means for rotating said shaft upon the movement of any of said levers in one direction; a mask having a plurality of slots each adapted to permit one of said levers to pass therethrough; and an escutcheon substantially parallel to said mask and having a series of slots substantially in register with the slots in said mask.

4. In a radio communication device having an assembly plate, a combination including: a frame mounted on said assembly plate and supporting a rotatable element; a bracket attached to said frame and extending through the plane of said plate; an escutcheon having a registering member extending substantially perpendicularly therefrom; said member having one edge abutting against said bracket.

5. In a mechanism for angularly positioning a control element of a radio device, a combination including: a rotatable shaft; a positionable lever mounted on said shaft; a pivoted operating member having a curved edge adapted to be longitudinally traversed by one end of said. positionable lever; said curved edge forming an arch between the points of engagement with said lever when said member is in the extreme position to which it may bemoved.

6. In a mechanism for angularly positioning a control element of a radio device, a combination including: a rotatable shaft; a positionable lever mounted on said shaft; 9. pivoted operating member having a curved edge adapted to be longitudinally traversed by one end of saidpositionable level; said curved edge forming an arch between the points of engagement with said lever when said member is in the extreme position to which it may be moved; and means for clamping said lever on said shaft, said means including a tightening screw; said screw forming an angle with a line connecting said points.

7. In a mechanism for angularly positioning a I control element of a radio device, a combination including: a train of gears; a first pulley attached to the gear at one end of said train; a second pul- Y ley attached to the gear at the opposite end of said train; said pulleys concentric with the gears to which they are attached and having the same ratio as said gears; a flexible connection between said pulleys; and means for keeping said connection taut, whereby the play in said gear train is removed.

8. In a mechanism for positioning a control of a radio apparatus, a combination including: an assembly frame; 'a rotatable member located inside said frame and disposed substantially parallel to the top thereof; a plurality of manually movable station selectors extending through a cover plate substantially perpendicular to the top of said frame; a plurality of angularly adjustable elements each operatively interposed between one of said selectors and said member and adapted upon movement of the associated selector to rotate said member to a position predetermined by the adjustment of said element; a resonancevarying device located above said frame; and instrumentallties for transmitting rotary motion from. said member to said device, said instrumen talities comprising a first rotatable element attached to said member, a second rotatable element attached to-said device, a third element operatively interposed between said first and second elements, and means for removing play from said instrumentalities.

9. In a mechanism for positioning a control of -a radio apparatus, a combination including: an assembly frame; a rotatable member located inside said frame and disposed substantially parallel to the top thereof; a plurality of manually movable station selectors extending through a cover plate substantially perpendicular to the top of said frame; a plurality of angularly adjustable elements each operatively interposed between oneof said selectors and said member and adapted upon movement of the associated selector to 7 said instrumentalities; said means comprising a spring having a connection to said first and second elements.

10. In a mechanism for positioninga control of a radio device, a combination including: a rotatable member; a plurality of independently operable position selectors; a plurality of elements each operatively interposed between one of said selectors and said member, and each adjustable with respect to said member in a plane substantially transverse thereto; each of said elements adapt ed upon operation of the associated selector to rotate said member to a. position predetermined by the adjustment of said element; a tuning sdale positioned symmetrically above said plurality of position selectors; an indicator adapted to cooperate with said scale; and means for producing relative motion between said scale and indicator upon rotation of said member; said means including a component fixed to said shaft between the planes of adjustment of two of said elements.

11. In a radio tuning apparatus, a combination including: an assembly frame; a positionable member rotatably mounted in said frame; a cover plate substantially parallel to said member; a plurality of manually movable station selectors extending through the plane of said plate; a plurality of angularly adjustable elements each operatively interposed between one of said selectors and said member and adapted upon movea resonance-varying device supported by said frame; a rotatable control for said device; and instrumentalities for transmitting rotary motion from said member to said control, said instruv mentalities comprising a first rotatable element connected to said member, a second rotatable element attached to said device, a third element operatively interposed between said first and second element, and means for removing play from said instrumentalities; said means comprising a spring having a connection to said first and second elements.

LE ROY J. LEISHMAN. 

